JP2001131563A - Organic waste gasification system - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide an organic waste gasification treatment system that can effectively utilize organic waste as a resource. SOLUTION: An exhaust heat recovery boiler 20 is connected to a downstream side of a gasification furnace 10, a hydrothermal reaction tube 30 is provided in the exhaust heat recovery boiler 20, and the pressure of the hydrothermal reaction tube 30 is raised to a subcritical pressure of water. The supplied organic waste 31 is supplied to cause a hydrothermal reaction, and the generated decomposition product is supplied to the gasification furnace 10 as fuel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic waste gasification treatment system using an integrated gasification combined cycle system.

[0002]

2. Description of the Related Art Conventionally, organic wastes such as garbage have been treated by a specialist company by methods such as collection, incineration, and landfill. In recent years, attempts have been made to turn organic wastes into resources. I have.

[0003] In the case of recycling organic waste as a resource, for example, a method of gasifying in a gasification furnace or the like, converting it into a gas containing CO and H ₂ as main components, and using it as a fuel or a chemical raw material is effective. is there.

[0004]

However, organic wastes such as orange scum and pulp sludge which have a high fibrous content and high viscosity, such as citrus scum and pulp sludge, are likely to be clogged in a gasifier burner. Many cannot be gasified as they are.

Japanese Patent Application Laid-Open No. 10-328699 discloses that oxidative decomposition of water-containing organic waste is carried out by a supercritical water oxidation reaction, and the use of this oxidatively decomposed gasified gas as combustion in a gasification furnace is not disclosed. Although it is possible, a heat source for supercriticality is required, and the pressure needs to be reduced to supply the gas to the gasification burner, and there is a problem of corrosion of the apparatus, which is not preferable.

Accordingly, an object of the present invention is to solve the above-mentioned problems and to provide an organic waste gasification treatment system capable of effectively utilizing organic waste as a resource.

[0007]

In order to achieve the above object, according to the present invention, an exhaust heat recovery boiler is connected downstream of a gasification furnace, and the exhaust heat recovery boiler is connected to a hydrothermal reaction tube. Organic waste gas, which is supplied to the hydrothermal reaction tube and supplied to the hydrothermal reaction tube to increase the sub-critical pressure of water to cause a hydrothermal reaction, and the generated decomposition products are supplied to the gasification furnace as fuel. It is a chemical processing system.

According to a second aspect of the present invention, the hydrothermal reaction tube is installed in an area where the exhaust gas temperature in the exhaust heat recovery boiler is 400 ° C. or less, and the organic waste pressurized to 80 to 130 kg / cm ² is provided. The organic waste gasification treatment according to claim 1, wherein the temperature is set to 280 to 340 ° C in the hydrothermal reaction tube, the water contained in the organic waste is made subcritical, and the organic waste is hydrothermally reacted. System.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a schematic diagram showing an organic waste gasification treatment system according to the present invention applied to an integrated gasification combined cycle system (IGCC).

[0011] In FIG. 1, 10, in the gasification furnace and reduced under the steam primarily with heavy oil burner 11 12 and oxidizing agent such as oxygen is supplied to the partial oxidation, H _2, CO And the like to generate a gasified gas.

Downstream of the gasification furnace 10, a gas purification system 13, a gas turbine 14, and an exhaust heat recovery boiler 2
0, the chimney 21 is connected sequentially.

First, the gasification gas generated in the gasification furnace 10 is dust-removed in a gas purification system 13 including a wet dust removal unit and a wet precision desulfurization unit, and hydrogen sulfide (H ₂ S) in the gasification gas is removed. Is removed to obtain a purified gasified gas, which is supplied to a combustor 15 of the gas turbine 14.

In the gas turbine 14, a compressor 16, a turbine 17, and a generator 18 are connected, a combustor 15 is connected between the compressor 16 and the turbine 17, and air compressed by the compressor 16 is supplied to the combustor 15. The gasified gas is burned, and the combustion gas drives the turbine 17 to generate electric power by the power generator 18.

The combustion exhaust gas from the turbine 17 is supplied to an exhaust heat recovery boiler 20 to recover the heat, and then the stack 21
It is designed to be exhausted from.

The exhaust heat recovery boiler 20 includes a flue gas passage 2
2, an inlet-side heat transfer tube 23 is provided on the downstream side, and an outlet-side heat transfer tube 24 is provided on the upstream side. The steam turbine 25 and the condenser 2 extend from the outlet-side heat transfer tube 24 to the inlet-side heat transfer tube 23.
6. The pump 27 is configured to be sequentially connected, and the feedwater is heat-exchanged with the combustion exhaust gas from the inlet-side heat transfer tube 23 to the outlet-side heat transfer tube 24 by the pump 27 to be turned into steam, and the steam turbine 25 is rotated. The generator 28 is driven, and is circulated again by the pump 27 from the condenser 26.

In the present invention, a hydrothermal reaction tube 30 is provided in the flue gas flow passage 22 between the inlet-side heat transfer tube 23 and the outlet-side heat transfer tube 24, and organic waste is provided on the inlet side of the hydrothermal reaction tube 30. A supply line 32 of the reactor 31 is connected to a booster pump 33, a decomposition line 34 is connected to the outlet side of the hydrothermal reaction tube 30, and the decomposition line 34 is connected to the burner 11 of the gasification furnace 10.

The hydrothermal reaction tube 30 is installed in an area where the exhaust gas temperature in the flow passage 22 in the exhaust heat recovery boiler 20 is 400 ° C. or less. At a pressure of 80 to 130 kg / cm ² .

Next, the operation of the present invention will be described.

The gasification gas generated in the gasification furnace 10 is
The gas is purified by dust removal, desulfurization, and supplied to a combustor 15 of a gas turbine 14 by a gas purification system 13. The fuel is combusted by the air pressurized by the compressor 16, supplied to the turbine 17, and the exhaust gas is recovered through the exhaust heat recovery boiler 20 and exhausted from the chimney 21.

The organic waste 31 contains about 3 organic substances.
0%, the remaining about 70% is water, which is supplied from the supply line 32 to the pressure pump 33 to 80 to 130 kg / c.
By raising the pressure to m ² and supplying it to the hydrothermal reaction tube 30, it is heated to 280 to 340 ° C. in the waste heat boiler 20, and the water in the organic waste is brought into a subcritical state. In the hydrothermal reaction in the hydrothermal reaction tube 30, the organic matter is decomposed by reacting with water,
Since it is converted into a compound or gas having a relatively small molecular weight, it can be treated as a liquid fuel.

Accordingly, the fuel can be supplied from the hydrothermal reaction tube 30 to the burner 11 of the gasification furnace 10 from the decomposition product line 34 and mixed with the heavy oil 12 for combustion.

Since the organic waste 31 is reduced in molecular weight by the hydrothermal reaction, clogging of the burner 11 does not occur.

The pressure in the gasification furnace 10 is about 20 to
30 kg / cm ² , and the pressure of the hydrothermal reaction tube 30 is high. Therefore, even if the pressure is adjusted by providing a back pressure adjusting valve in the decomposition product line 34, or a decomposition such as an ejector is performed before the burner 11. It is also possible to provide a mixer for the heavy oil and the decomposed product and to supply the heavy oil and the decomposed product to the burner 11 using the pressure of the decomposed product.

[0025]

In summary, according to the present invention, the organic waste is hydrothermally reacted by using the waste heat boiler of the integrated gasification combined cycle system and supplied to the gasification furnace, whereby the organic waste is discharged. Can be used effectively.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Gasifier 12 Heavy oil 13 Gas purification system 14 Gas turbine 15 Combustor 17 Turbine 20 Exhaust heat recovery boiler 30 Hydrothermal reaction tube 31 Organic waste 32 Supply line 33 Boost pump 34 Decomposition line

Continued on front page F-term (reference) 4D004 AA01 AA03 AA04 AC05 BA03 CA27 CA39 CA50 CC03 DA03 DA06 DA07 4G075 AA05 AA41 AA63 CA02 CA05 CA61 CA65 CA66 DA01 DA18 EA06 EB21

Claims (2)

[Claims] 1. An exhaust heat recovery boiler is connected downstream of a gasification furnace, a hydrothermal reaction tube is provided in the exhaust heat recovery boiler, and the organic waste is pressurized to a subcritical pressure of water in the hydrothermal reaction tube. An organic waste gasification treatment system, comprising supplying a substance to cause a hydrothermal reaction, and supplying a generated decomposition product as a fuel to a gasification furnace. 2. A hydrothermal reaction tube is installed in an area where the temperature of exhaust gas is 400 ° C. or less in an exhaust heat recovery boiler,
The organic waste pressurized to 30 kg / cm ² is heated to 280 to 340 ° C. in a hydrothermal reaction tube to make the water contained in the organic waste subcritical, and the organic waste undergoes a hydrothermal reaction. The organic waste gasification treatment system according to claim 1.